Generally speaking, photographic images obtained from silver halide photographic light-sensitive materials are not permanent and gradually deteriorate with the passage of time. In particular, color images formed by azomethine dyes or indoaniline dyes produced by the reaction between an oxidation product of an aromatic primary amine developing agent and a coupler, when exposed to light for a long time or preserved in a high temperature and high humidity atmosphere, usually undergo decoloration or discoloration of image areas and also discoloration of the non-image areas, i.e., white background, resulting in deterioration of image quality.
Such deterioration of image quality is a serious defect for recording materials. Various compounds have been proposed in order to overcome this problem, but none of them has succeeded in producing the desired effect.
For example, conventionally known compounds which have been used for preventing decoloration or discoloration of color images include hydroquinone derivatives, e.g., 2,5-di-t-butylhydroquinone as is described in U.S. Pat. Nos. 2,360,290, 2,418,613, 2,700,453, 2,701,197, 2,728,659, 2,732,300, 2,735,765, 3,982,944, 4,430,425, 2,710,801 and 2,816,028; phenol compounds, e.g., 2,6-di-t-butyl-p-cresol, 4,4'-methylenebis(2,6-di-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol) or 4,4'-isopropylidenediphenol as is described in U.S. Pat. Nos. 2,735,765, 3,700,455 and 4,228,235; British Pat. No. 2,066,975; Japanese Patent Publication Nos. 19764/82 and 6623/77 and Japanese Patent Application (OPI) No. 10539/84; compounds obtained by substituting a hydroxyl group of couroman derivatives such as tocopherols or dihydroxyindane derivatives as is described in U.S. Pat. Nos. 3,432,300, 3,573,050, 3,574,627, 3,698,909, 3,764,337 and Japanese Patent Application (OPI) No. 15222/77 with an alkoxy group, an acyloxy group or a silyl group; and methylenedioxybenzene derivatives and aminophenols as is described in U.S. Pat. Nos. 3,457,079 and 4,332,886, and Japanese Patent publication No. 21144/81. However, some of these compounds fail to produce the desired effect although a certain effect may be achieved; or some of them have adverse effects, such as deterioration in hue, generation of fog, poor dispersion, crystallization, and the like, despite their effect of preventing decoloration. Therefore, they are unsatisfactory as color image stabilizers having synthetically excellent effects.